Final answer:
When a cell is placed in an isotonic solution, water moves equally in and out of the cell, preventing any significant changes in cell volume. The cell will not burst or become dehydrated, contrary to what might occur in hypotonic (swelling and bursting) or hypertonic (shrinking) environments.
Step-by-step explanation:
If a cell is placed in an isotonic solution, the concentration of dissolved materials (solutes) is equal both inside and outside of the cell. This balance means that water will move across the cell membrane at a rate that maintains equilibrium, with no net gain or loss of cellular water content. Therefore, osmosis will still occur as water molecules continue to move in and out of the cell, but the cell will not experience any dramatic volume changes. As such, none of the scenarios presented (A: the cell bursting, or C: the cell becoming dehydrated) would occur in an isotonic environment. Instead, the cell would remain stable, retaining its normal shape without the risk of bursting or dehydration.
In contrast, in a hypotonic solution, a cell would swell with the influx of water and might burst if the membrane cannot contain the increased volume, which is often the case in animal cells without a rigid cell wall. A hypertonic solution, on the other hand, has a higher concentration of solutes outside the cell than inside, leading to water exiting the cell, which can result in cell shrinkage and plasmolysis, especially noticeable in plant cells.